W+W- Hadronic Decay Properties

Recent measurements of the properties of W+W- events produced in e+e- collisions at Ecm=183 GeV at LEP are reviewed. The data are used to investigate the predicted effects of final state interactions, specifically "colour reconnection".Comment: 6 pages, 7 figures. To appear in the "Proceedings of the XXIX International Conference on High Energy Physics", Vancouver, CA, 23-29 July 199

Experimental aspects of colour reconnection

This report summarises experimental aspects of the phenomena of colour reconnection in W+W- production, concentrating on charged multiplicity and event shapes, which were carried out as part of the Phenomenology Workshop on LEP2 Physics, Oxford, Physics Department and Keble College, 14-18 April, 1997. The work includes new estimates of the systematic uncertainty which may be attributed to colour reconnection effects in experimental measurements of Mw.Comment: 10 pages, 4 figures. To be published in proceedings of Phenomenology Workshop on LEP2 Physics, Oxford 14-18 April 199

The impact of stochastic physics on climate sensitivity in EC-Earth

Stochastic schemes, designed to represent unresolved sub-grid scale variability, are frequently used in short and medium-range weather forecasts, where they are found to improve several aspects of the model. In recent years, the impact of stochastic physics has also been found to be beneficial for the model's long term climate. In this paper, we demonstrate for the first time that the inclusion of a stochastic physics scheme can notably affect a model's projection of global warming, as well as its historical climatological global temperature. Specifically, we find that when including the 'stochastically perturbed parametrisation tendencies' scheme (SPPT) in the fully coupled climate model EC-Earth v3.1, the predicted level of global warming between 1850 and 2100 is reduced by 10% under an RCP8.5 forcing scenario. We link this reduction in climate sensitivity to a change in the cloud feedbacks with SPPT. In particular, the scheme appears to reduce the positive low cloud cover feedback, and increase the negative cloud optical feedback. A key role is played by a robust, rapid increase in cloud liquid water with SPPT, which we speculate is due to the scheme's non-linear interaction with condensation.Comment: Under review in Journal of Geophysical Research: Atmosphere

Don’t get involved: an examination of how public sector organisations in England are involving disabled people in the Disability Equality Duty

The Disability Equality Duty (DED) came into force in December 2006. It stipulated that all public sector organisations were to develop policies to promote the equality of disabled people as staff members, consumers or visitors. Its emergence comes as part of a network of social policies developed over the last 20 years to promote disability rights and citizenship in the UK. However unlike previous legislation, the DED set in place the need for organisations to be pro-active in their policies and work with disabled people to move towards change in public sector cultures and working practices. This article reports on this early stage of implementation in England. Findings show that whilst some progress has been made in securing change, practice varied greatly. Therefore if a fundamental change in the culture of work and service provision is to be secured, this key requirement will need to be given a higher priority by organisations

Hadronic unquenching effects in the quark propagator

We investigate hadronic unquenching effects in light quarks and mesons. Within the non-perturbative continuum framework of Schwinger-Dyson and Bethe-Salpeter equations we quantify the strength of the back reaction of the pion onto the quark-gluon interaction. To this end we add a Yang-Mills part of the interaction such that unquenched lattice results for various current quark masses are reproduced. We find considerable effects in the quark mass function at low momenta as well as for the chiral condensate. The quark wave function is less affected. The Gell--Mann-Oakes-Renner relation is valid to good accuracy up to pion masses of 400-500 MeV. As a byproduct of our investigation we verify the Coleman theorem, that chiral symmetry cannot be broken spontaneously when QCD is reduced to 1+1 dimensions.Comment: 27 pages, 15 figures, minor corrections and clarifications; version to appear in PR

Delayed soft X-ray emission lines in the afterglow of GRB 030227

Strong, delayed X-ray line emission is detected in the afterglow of GRB 030227, appearing near the end of the XMM-Newton observation, nearly twenty hours after the burst. The observed flux in the lines, not simply the equivalent width, sharply increases from an undetectable level (<1.7e-14 erg/cm^2/s, 3 sigma) to 4.1e-14 erg/cm^2/s in the final 9.7 ks. The line emission alone has nearly twice as many detected photons as any previous detection of X-ray lines. The lines correspond well to hydrogen and/or helium-like emission from Mg, Si, S, Ar and Ca at a redshift z=1.39. There is no evidence for Fe, Co or Ni--the ultimate iron abundance must be less than a tenth that of the lighter metals. If the supernova and GRB events are nearly simultaneous there must be continuing, sporadic power output after the GRB of a luminosity >~5e46 erg/s, exceeding all but the most powerful quasars.Comment: Submitted to ApJL. 14 pages, 3 figures with AASLaTe

Optical/IR studies of Be stars in NGC 6834 with emphasis on two specific stars

We present optical and infrared photometric and spectroscopic studies of two Be stars in the 70--80-Myr-old open cluster NGC 6834. NGC 6834(1) has been reported as a binary from speckle interferometric studies whereas NGC 6834(2) may possibly be a gamma Cas-like variable. Infrared photometry and spectroscopy from the United Kingdom Infrared Telescope (UKIRT), and optical data from various facilities are combined with archival data to understand the nature of these candidates. High signal-to-noise near-IR spectra obtained from UKIRT have enabled us to study the optical depth effects in the hydrogen emission lines of these stars. We have explored the spectral classification scheme based on the intensity of emission lines in the $H$ and $K$ bands and contrasted it with the conventional classification based on the intensity of hydrogen and helium absorption lines. This work also presents hitherto unavailable UBV CCD photometry of NGC 6834, from which the evolutionary state of the Be stars is identified.Comment: Published in Research in Astronomy and Astrophysics, RAA 14 (2014) 1173-1192, 20 pages, 10 figure

FLUKA Simulations of Energy Density Deposition from a ILC Bunch in different Spoiler Designs

FLUKA is used to simulate the energy deposition due to a direct bunch impact of the ILC beam in various candidate spoiler designs. The conclusions extracted will contribute to the overall optimisation process and identify areas where additional experimental data would be beneficial

FearNot! An Anti-Bullying Intervention: Evaluation of an Interactive Virtual Learning Environment

Original paper can be found at: http://www.aisb.org.uk/publications/proceedings.shtm

L & M band infrared studies of V4332 Sagittarii - detection of the water-ice absorption band at 3.05 microns and the CO fundamental band in emission

L and M band observations of the nova-like variable V4332 Sgr are presented. Two significant results are obtained viz. the unusual detection of water ice at 3.05 microns and the fundamental band of 12CO at 4.67 microns in emission. The ice feature is a first detection in a nova-like variable while the CO emission is rarely seen in novae. These results, when considered together with other existing data, imply that V4332 Sgr could be a young object surrounded by a circumstellar disc containing gas, dust and ice. The reason for a nova-like outburst to occur in such a system is unclear. But since planets are believed to form in such disks, it appears plausible that the enigmatic outburst of V4332 Sgr could be due to a planetary infall. We also give a more reliable estimate for an epoch of dust formation around V4332 Sgr which appears to have taken place rather late in 1999 - nearly five years after its outburst.Comment: 10 pages, 3 figures (to appear in ApJ(Letters), 2004